Elevator systems are useful for carrying passengers, cargo, or both, between various levels in a building. Some elevators are traction based and utilize load bearing members such as ropes or belts for supporting the elevator car and achieving the desired movement and positioning of the elevator car.
Where ropes are used as load bearing members, each individual rope is not only a traction device for transmitting the pulling forces but also participates directly in the transmission of the traction forces. Where belts are used as a load bearing member, a plurality of tension elements are embedded in a common elastomer belt body. The tension elements are exclusively responsible for transmitting the pulling forces, while the elastomer material transmits the traction forces. In some belts, the tension members are cords formed from a plurality of elements such as steel wires, while in other belts the tension members may be formed from unidirectional fibers arranged in a rigid matrix composite, providing significant benefits when used in elevator systems, particularly high rise systems. Fire resistance is an important safety element associated with belt performance.